A MAN who attacked his partner's colleague because he thought they had been flirting is behind bars.

Simon Mowbray - who trains at boxing twice a week - broke the jaw of his victim after storming into their workplace.

Earlier, he had seen text messages on her mobile phone and "jumped to a conclusion", Teesside Crown Court heard.

Judge Peter Bowers told the 28-year-old supermarket worker: "It was obviously a case of red mist descending."

The judge described the reason for the out-of-character attack as "insane" and said it was text message "banter".

Jim Withyman, mitigating, said father-of-three Mowbray, of Cheviot Crescent, Billingham, had never before been in trouble.

"He is truly remorseful," said Mr Withyman. "He has shocked himself. He will never do anything like this again.

"He will never put his family, his children, in a position where he faces going to prison, as he does today.

"He accepts he rained a number of blows on the complainant. It was a very, very short assault, a moment of madness."

Mr Withyman pleaded with the judge not to jail Mowbray because of a series of glowing references and his good character.

"It was an impulsive act," added the barrister. "He has revulsion for what he has done. He is shocked by his conduct."

Judge Bowers said he was reducing the jail sentence to two years and three months to reflect Mowbray's good points.

But he told him: "You jumped to a conclusion, and rather than confront your partner, you simply took the law into your own hands and attacked him in a vicious way."

The court heard that the victim was taken to hospital where doctors planned to operate, wire his jaw and remove teeth.

In an impact statement, he said: "I feel completely shocked by this incident. It was an unprovoked attack at my place of work.

"I feel it was pre-planned by Mowbray. I am going to lose my trust in people, and my livelihood."

The court heard how the victim no longer works at the florists, which is owned by the father of Mowbray's long-term partner.

Mowbray admitted a charge of inflicting grievous bodily harm with intent at an earlier court hearing.